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Best failed neurological tests last week, according to Anwar S. Richardson of MLive.com. Richardson cited sources saying the Lions didn't anticipate Best being cleared and that the team wanted him to accrue another NFL season in order to have access to the NFL's pension plan.

"After today's consultation with medical experts, including representatives from our medical and training staffs, it has been determined that Jahvid will not be permitted to return to return to play at this time," Mayhew said in a statement released by the team. "While today's decision is disappointing from a football perspective, we fully and entirely respect and support this recommendation.

"Jahvid will continue to work with out medial and training staffs with the hope that he ultimately will be cleared to return to the playing field."

This isn't a surprise, considering there was no news after Best went through post-concussion tests last week. Best hasn't played a down since Oct. 16, 2011 and was plagued with concussion issues in college.